Bash 解法, 执行用时: 2ms, 内存消耗: 424KB, 提交时间: 2021-12-20

#!/bin/bash
while read line
do 
arr=(${line//./ })
if [ ${#arr[*]} -ne 4 ];then
printf "error\n"
else
for((i=0;i<${#arr[*]};i++))
do
[ ${arr[${i}]} -gt 255 ] && printf "no\n" && break
done
[ $i == 4 ] && printf "yes\n"
fi
done < nowcoder.txt

Bash 解法, 执行用时: 2ms, 内存消耗: 436KB, 提交时间: 2022-02-09

# copied from discussion
while read line
    do
        arr=(${line//./ })
        if [ ${#arr[*]} -ne 4 ];then
                printf "error\n"
            else
                for ((i=0; i<${#arr[*]}; i++))
                    do
                        [ ${arr[${i}]} -gt 255 ] && printf "no\n" && break
                    done
                    [ $i == 4 ] && printf "yes\n"
        fi
    done

Bash 解法, 执行用时: 3ms, 内存消耗: 400KB, 提交时间: 2022-02-28

# awk -F "." '{
#     if (NF == 4) {
#         for (i = 1;i < 5;i++) {
#             if ($i > 255 || $i < 0) {
#                 print("no");break;
#             } 
#         }
#         if (i == 5) {print("yes")}
#     } else {
#         print("error")
#     }
# }'

while read line
do
    sum=0
    IFS=.
    arr=($line)
    if [ ${#arr[@]} -lt 4 ]
    then
        echo 'error'
    else
        for i in ${arr[@]}
        do
            if [ $i -ge 0 -a $i -le 255 ]
            then
                ((sum+=1))
            fi
        done
        if [ $sum -eq 4 ]
            then
                echo 'yes'
            else
                echo 'no'
        fi
    fi
done < nowcoder.txt

Bash 解法, 执行用时: 3ms, 内存消耗: 408KB, 提交时间: 2021-12-20

# awk '{
#     if ($0 ~ /^((25[0-5]|2[0-4][0-9]|1[0-9][0-9]|[1-9][0-9]|[0-9])\.){3}(25[0-5]|2[0-4][0-9]|1[09][0-9]|[1-9][0-9]|[0-9])$/) {
#         print("yes");
#     } else if ($0 ~ /[[:digit:]].[[:digit:]].[[:digit:]].[[:digit:]]/){
#         print("no");
#     } else {
#         print("error")
#     }
# }' nowcoder.txt

# awk -F '.' '{
#     if (NF == 4) {
#         for (i = 1; i < 5; i++) {
#             if ($i > 255 || $i < 0) {
#                 print("no")
#                 break
#             }
#         }
#         if (i == 5) {
#             print("yes")
#         } else {
#             print("error")
#         }
#     }
    
# }'

IFS='.'
while read line; do
    arr=(${line})
    if [ ${#arr[*]} -ne 4 ]; then
        printf "error\n"
    else
        for ((i = 0; i < ${#arr[*]}; i++)); do
            if [ ${arr[${i}]} -gt 255 ]; then
                printf "no\n"
                break
            fi
            done
#         if [ $i == 4 ]; then
#             printf "yes\n"
#         fi
        [ $i == 4 ] && printf "yes\n"
    fi
done

Bash 解法, 执行用时: 3ms, 内存消耗: 412KB, 提交时间: 2022-02-25

IFS='.'
while read line; do
    arr=(${line})
    if [ ${#arr[*]} -ne 4 ]; then
        printf "error\n"
    else
        for ((i = 0; i < ${#arr[*]}; i++)); do
            if [ ${arr[${i}]} -gt 255 ]; then
                printf "no\n"
                break
            fi
            done
        [ $i == 4 ] && printf "yes\n"
    fi
done